Improvement in rock-drilling machines



2 Sheet--Sheet 1.

Rock-Drilling Machines.

Patented April 23, 1872.

- Jo a-14 .l/r/ I 2 Sheets--Shee1 2'. A. D. WILLIAMS.-

lmprovement in Rock-Drilling Machines-k N0. l25,923, Patented April23 i 8-72.

UNITED STATES ARTHUR DAVID WILLIAMS, OF LONDON, ENGLAND.

IMPROVEMENT IN ROCK-DRILLING MACHINES.

Specification forming part of Letters Patent No. 125,923, dated April 23, 1872.

SPEomrcATIoN.

To all whom it may concern:

Be it known that I, ARTHUR DAVID WIL- LIAMS, of Scotts Chambers, Pudding Lane, in the city of London, England, have invented certain Improvements in Machinery for Drilling; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawing making part of this specification, in which- Figure 1 is an elevation of the drilling de vices mounted in a clamping standard. Fig. 2 is a top view of the drilling devices as seen by making a horizontal section through the upper portion of the standard. Figs. 3 and 4 are details of the feed mechanism.

Similar letters of reference indicate corresponding parts in the several figures.

This invention relates to certain improved devices for drilling, wherein a tool is employed which is actuated by pressure applied in the direction of its axis, such pressure being adjustable at the will of the operator, but constant when adjusted.

The apparatus represented in thedrawing is designed to be operated by hand or other power applied to the shaft carrying the boring-tool,

which shaft has a coarsepitched thread thoughout its entire length, which is received between and engages with threads out upon two worm-wheels. To these worm-wheels adjustable brakes are applied, intended to operate as a retarding force proportioned to the power drivingthe apparatus, the efl'ect of which will be that the thrust of the screw-shaft or borer is received by the .wormwheels, and they will rotate or slip at a rate proportioned to the diiference between the power driving the apparatus and the resistance met with by the borer, and thus an automatic feed is obtained.

The following particular description will enable others skilled in the art to carry my invention into efl'ect.

In the annexed drawing, Figure 1 shows the apparatus mounted on a standard, which is designed to be fixed between two opposite bearing-surfaces. The standard, which is tubular, is formed of two parts, the upper part, A, bein g double and surmounted by a rocking clawpiece, a, attached to the part A by a conical swivel-joint. The lower end is formed into a collar, a, through which the lower part B passes and is secured by a cotter passing through suitable holes in the collar a and tube B. They can be fixed at various points, and the standard can be thus varied in length. Additional variation can be obtained by means of an adjusting-screw, b, which is tapped into the lower end of the tube B, and to which is applied a claw-foot, 1). Between the parallel bars of the upper part A of the standard is fixed, by means of two sliding clip-collars, c c, a metal box, N, containing worm-wheels D D forming the automatic feed, between which the driving screw-shaft 0 works. Any desired direction can be given to the screw 0 and its borer by means of conical clamp-trunnions, shown in Figs. 2 and 4, which trunnions attach the metal box N to the bars of standard section A, in conjunction with the sliding clip-collars c c and a conical swivel-joint. At one end of the screw-shaft G is fixed a socket piece carrying the borer O, and to the opposite end of this shaft is attached a ratchethandle or other device, by means of which the borer is driven.

I will now explain the automatic feed mechanism contained in the adjustable box N, through which latter the screw-shaft 0 passes, reference being hadto the enlarged scale, Figs: 3 and 4, of which Fig. 3 is a side view of the box N with one side removed. Fig.4is a sectional plan of one-half of the box and the mechanism contained therein. shaft passes between and engages with the teeth of two hollow wheels, D D, which are fixed on axles working in the sides of box N. Inside of each wheel is a metal band, P, one end of which is attached to the box N by a pin. The other end of this band I? is attached to a connection, f, of the form shown, which connection, by means of a screw, g, can be made to traverse endwise, and thus to expand the band P, bringing it, with any required pressure, in contact with a lining of leather, 6 or other suitable material, covering the in ner flan ged surface of its worm-wheel.

When the apparatus is in operation pressure, proportioned to the power driving the main screw 0, is put upon the wheels D D by means of the screw g with its connection f,

which expands the metal bands or brakes P 1?. When the thrust of screw 0 is greater The screwthan the retarding pressure applied by the metal bands or brakes to the wheels D D, the latter revolve, and thus regulate the advance movement to the said screw and its borer in proportion to the resistance encountered by the borer. By releasing the wheels D D from the brake pressure when the hole is bored the required depth, the screw 0 can be drawn through the wheels D D, which are then free to revolve, and thus the borer with the debris is withdrawn direct firom the hole.

If desired, handles can be applied to the ends of the shafts of wheels D D, for the purpose of withdrawing the screw-shaft andborer.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is-- 1. The arrangement of the brakes P P within their spur-wheels, so as to act outwardly Witnesses:

EDMUND EDWARDS, CHARLES J muss WINTERSGILL. 

